X-ray table with tilted tube



June 18, 1963 A. PALERMO, JR., ETA L 3,

X-RAY TABLE WITH TIL-TED TUBE 2 Sheets-Sheet 1 Filed Feb. 10. 1961 INVENTORS EDWARD B. GRAVES ANTHONY PALERMOJR. mm ,1 Mm

Attys.

June 18, 1963 A: PALERMO, JR., ETAL 1 X-RAY TABLE WITH TILTED TUBE Filed Feb. 10, 1961 2 Sheets-Sheet 2 FIG. 4 57 EDWARD B5%"E" F IG. 3 BY ANTHONY PALERMOJR.

United States Patent X-RAY This invention relates to X-ray apparatus and more pazglticu larly to the X-ray tables of the type known as tilt In medical X-ray examination of human patients, to determine the state of physical well being of the patient specially designed X-ray tables are used which provide a support surface upon which the patient can lie in a prone p 0S1t10I'1. In one class of table an X-ray tube is posi tioned within the body of the table and below the supporting top table surface. This tube emits a .beam of X-rays which are directed upwardly through the table top for examination of a patient.

A device known as a fluoroscopic column or tower is carried on suitable guides within the table body. This column is movable relative to the support surface along paths which are both longitudinal and transverse with respect to the surface. The X-ray tube is supported by this column and moves with it. Usually a mechanism 1s mounted on the column for movement along the column toward and away from the support surface. Such mechanisms are known as spot film devices.

The spot film device is positioned in the path of a beam of X-rays emitted by the tube and on the side of the support surface opposite the X-ray tube. The usual spot film device will have both a fluoroscopic screen for fluoroscopic examination of a patient and a carrier mechamsm for carrying a suitable film holder such as a cassette. The carrier is selectively movable into and out of the path of X-rays for radiographic exposure of a film carried in the cassette.

Usually modern X-ray table bodies are supported for movement of the supporting surface in one direction from a horizontal position to a vertical position where the patient is upright. The table bodies are also movable 1n the opposite :direction. In US. Patent No. 2,872,584 to R. C. Schiring et al., for an X-ray Apparatus, a so-called 90-90 table is shown in which the table body is tiltable from the horizontal position 90 in either direction to the vertical. Other types of mechanisms for tilting table bodies are well known in the art both for the provision of 90-90 tables and the provision of tables which are tiltable for example in one direction to a vertical position and in the other direction to a socalled Trandelenber-g position.

The invention presented "here is applicable for most any of these various types of tilt tables and it is shown 1n its preferred form with a tilting mechanism similar to that taught in the Schiring et al. patent.

In the Schiring et al. apparatus the table body is supported on a pedestal. When moved from the horizontal to the vertical position the body is simultaneously tilted and shifted translationally relative to the pedestal. The purpose of this simultaneous shifting and tilting is so that the support surfaces may be as low as possible with a table body which is tiltable. Thus, the limiting factors in determining how low a table can be are: (1) the depth of the body required to place the X-ray tube the required distance below the table support surface, and (2) the provision of a tilting mechanism which can tilt the body without the body striking the floor or pedestal or the like.

The provision of a table which is as low as possible is an important consideration to radiologists and their assistants. The radiologist and his assistants must be able to easily see the image presented on the fluoroscopic screen when a patient is lying prone on a horizontally disposed surface and the screen is above the patient. Clearly this is a rather difiicult objective if the radiologist is short and the patient is large.

With the mechanism of this invention a substantial improvement in table height is obtained. An X-ray tube of the rotating anode type is carried in a housing beneath the table. The tube and housing provide the advantages which permit the obtainment of a lower table. The tube is constructed such that the target area on the anode is remote from the table support surface. Thus a beam of X-rays is emitted from a target area on the lower side of the tube and the beam passes through the tube and out a window on the side of the tube remote from the target area.

The tube is positioned in a housing which is mounted at an angle with respect to the table supporting surface so that the longitudinal axis of the housing and preferably coincident axis of rotation of the anode are at an angle with the surface. This permits the X-ray beam to travel from the target area remote from the X-ray window in the housing through the window without excessive shadow being caused by the anode structure, the mechanism for connecting the target to the remainder of the anode and the like.

The described arrangement permits the lowering of the table top for two reasons. It permits the lowering of the top relative to the tube while maintaining the same target-to-top distance because the target is on the remote side of the X-ray tube. Additionally the tilting of the tube housing reduces the space required in the table body for any selected amount of longitudinal travel. This is both because (1) the tilting of the housing shortens its effective longitudinal length and (2) the lower portions of the table :ends can be slanted inwardly more than was previously possible without affecting the amount of longitudinal tube travel. Thus the entire table :body can be lower because the clearance problem of tilting is reduced when the lower ends of the housing are so slanted.

Another of the features of the invention resides in the housing in which the X-ray tube is encased. This housing is within the body. It is connected to the column and moves with it. This housing includes a hollow central portion that carries the Xray tube. The tube has electrical connections at opposite ends of the housing central portion. The housing also includes a pair of arms which receive and retain end connectors on a pair of high tension electrical cables.

The arms are positioned on opposite sides of the central portion and are positioned such that the cable connectors parallel the longitudinal axis of the housing and of the tube. The arms are directed in opposite directions terminating at locations which are relatively near the longitudinal mid-point of the housing. In this way the loads imposed by the cables are symmetrically disposed in a balanced fashion so that easy column movement is obtained. In addition the cables are free and clear of the body and the like in all column positions so that the described advantages of a lower X-ray table are fully realized without cable interference.

Other advantages and a fuller understanding of the invention may be had by referring to the following description and claims taken in conjunction with the accompanying drawing in which:

FIGURE 1 is a front elevational view of an X-ray table;

FIGURE 2 is a sectional view of an end portion of the table body, which end is the left hand end portion in FIGURE 1, on an enlarged scale with respect to FIG- URE l and as seen from a longitudinal plane of cross section;

FIGURE 3 is a sectional View of the rearward portion of the table body on the scale of FIGURE 2 and as seen from a transverse plane of cross section; and,

FIGURE 4 is a sectional view of the improved tube housing as seen from a longitudinal plane of cross section and on an enlarged scale with respect to the other drawings.

Referring now to the drawings and to FIGURE 1 in particular, a pedestal is shown generally at iii. A portion of the pedestal houses a drive mechanism, portions of which are shown in dotted lines at 11. This drive mechanism 11 selectively causes translational movement of a table body 1-2, relative to the pedestal it and simultaneous tilting from the horizontal position shown. This tilting mechanism may be the mechanism taught in the referenced Schiring et a1. Patent No. 2,872,584 which provides tilting of 90 in either direction from the horizontal position.

The table body 12 includes a support surface 13 on which a patient is positioned. The usual spot film device is provided at 14 above and spaced from the support surface 13. The spot film device 14 may be of the type described in greater detail in U.S. Patent No. 2,749,445. This spot film device includes a fluoroscopic screen 15 and a means within the device to selectively position an X-ray film in an exposure position. The spot filmer is carried on a column 117 for relative movement along a path toward and away from the support surface 13.

The column 17 includes an inwardly extending supporting carrier 18 which is disposed in part within the table body 12. The column carrier 18 extends through a slot 19 which is provided at the back of the table. The column carrier 13 is supported by rollers 21 which ride on a carriage 20. The carrier 18 is reciprocable on the carriage 2e transversely of the body.

The carriage 26 is reciprocally mounted in the body 12 on rollers 22 which coact with guides 23. The carriage is movable along a longitudinal path which is parallel to the support surface 13. The column carrier 18 is, of course, movable longitudinally with the carriage 29. As will be apparent, the longitudinally extending opening 19 at the back of the table is of sufiicient longitudinal extent to permit free longitudinal travel of the carriage 20 and the elements supported by it.

An X-ray tube housing is shown generally at 25. The housing 25 is connected by a support member 26 to the column carrier 18. The support member 26 is preferably in the shape of an inverted frustum of a pyramid. The support member is so shaped to permit free passage of the usable portion of an emitted beam of X-rays, and to provide a portion of the shielding for the operator and the patient from that portion of the emitted rays which are not used and from so called scatter radiation. This usable portion of the emitted beam and the support member 26 are, in the customary manner, positioned symmetrically about an imaginary line normal to the support surface 13.

The X-ray tube housing 25 includes an elongated cen tral portion 27. The central portion 27 has a longitudinal axis which is disposed in a plane which is normal to the table top 13. The longitudinal axis of the housing-central portion 27 is at an angle with the table top so that one end, the left in FIGURE 2, 28 is higher than the opposite end 29. The longitudinal axis of the central portion 27 is preferably at an angle of about 15 with the plane of the table top 13.

The housing central portion 27 includes an X-ray aperture or window 30, FIGURE 3, at the top thereof. An X-ray tube 31 is positioned in a cavity in the housing central portion 27 and located to emit a beam of X-rays through the housing window 30. The tube 31 is preferably of the rotating anode type. That is, the tube has an anode assembly which includes a motor armature 32 driven by induction windings 33. The windings 33 are external of a glass X-ray tube insulator 34.

The anode assembly also includes a target 35 which is carried on the inner end of the anode assembly. The target 35 of this tube is the reverse of the usual tube. That is, the target 35 is a frusto-conically shaped member with a target area 36 on the inner concave surface of the target 35. The target area 36 is struck by a flow of electrons emitted by a suitable cathode 37. As is best seen in FIG- URES 2 and 4, the cathode 37 and the target 36 are preferably symmetrical about a plane normal to the table top 13 and located by the axis of rotation of the anode and the preferably coincident longitudinal axis of the housing. The target area 36 and the cathode 3'7 are positioned below the axis of anode rotation such that the axis is between the target area 36 and the table top. Thus, the

. target area is on the side of the X-ray tube remote from the housing X-ray window 30. With this construction and a tube of given size positioned a given distance from the table top, the target-to-top distance will be about 2 inches greater than a table with the usual tube positioned this same given distance from the table top.

The tilted housing permits an X-ray beam generated on such a remote X-ray target to be emitted from the window of the tube without any problem of a so-called shadow being cast by the remainder of the target and its supporting assembly. Additionally, as is best seen in FIGURE 2, the tube nests nicely at one end of the table permitting an abrupt slanting in of the end of the table at the location indicated by the numeral 46. The table is cut away at 40 far more than has been previously possible but the same longitudinal tube travel as has been available in the past is obtained. Further, the tilting of the tube housing 25 shortens the effective longitudinal length of the housing and further reduces the amount of space required in the table for any given amount of longitudinal housing travel.

Another of the features of the invention resides in the arrangement of the cable connections. The housing includes anode and cathode arms 41, 42. These arms have female electrical connection receptacles 43, 44 which receive m'ale'cable connectors 45, 416. The cable connectors 45, 46 are end connections for high-tension cables 47, 43 respectively.

The anode and cathode receptacles 43, 44 are respectively connected to the Xray tube by bus-bar-like con- 'ductors 49, 50. These conductors 49, 59 are positioned in passageways at the ends of the housing. These passageways communicate with the X-ray tube housing cavity.

The arms 41, 42 respectively terminated at ends 51, 52. These ends 51, 52 include the connector receiving openings to the electrical cable receptacles 43, .4 respectively. The arm ends 51, 52 are each positioned relatively near the housing central portion. The arms are oriented in opposite directions with the receptacles 43, 44 each having an axis paralleling the common axis of the housing central portion 27 and the X-ray tube 31.

As is best seen in FIGURE 4, the housing is made of "a number of parts which are fabricated into two principal sections. The anode arm 41 and the anode end part of the housing central portion 27 comprise the first of these sections. In the preferred and disclosed arrangement this first section is a unitary cast section designated by the numeral 54.

The second section is composed of a middle part 55, which is the middle part of the housing central portion 27, a cathode part 56, which includes the cathode arm 42, a cathode end part of the housing central portion 27, and a cathode end cap 57. The middle part 55 and the cathode end part 56 are welded together at 58 to fabrica'te a unitary section. The anode section 54 includes an annular mounting flange 59 which is bolted to the middle part 55 of the second or cathode section.

With this described construction, the two housing sections are rotatable relative to one another so that the relative position of the arms 41, 42 can be adjusted. In the embodiment shown and in most X-ray table applications, these arms 41, 42 are disposed on opposite sides of, and equal distances from an imaginary plane located by the axis of the housing central portion 27 and normal to the support surface 13. The arms are so disposed to provide a balanced cable load on the housing support. Where special situations require it, the anode sections may be rotated relative to the cathode section and then secured in a desired position to provide full and complete clearance of the cables 47, 48. Further flexibility for special situations is provided because the cathode part 56 may have an infinite number of positions relative to the middle part 55. In the preferred and disclosed construction these relative positions must be permanently selected before the weld 58 is made. Such special situations would include the situation when other accessories or the like are in the table which may interfere with the cables and when the housing is used above an X-ray table on a so-called ceiling tube mount.

With the unique housing construction which has been described there is a minimized interference with the freedom of movement of the column 17 and its connecting parts. Thus minimizing of interference of column movement further enhances the space requirements within the table and therefore further contributes to a compact table body and the attendant advantages of a lower table top. 7

While the invention has been described with a great deal of detail it is believed that it essentially comprises an X-ray table including a body and a column mounted in the body for relative longitudinal and transverse movement, an X-ray tube housing on the column, and disposed within the body, the housing has a longitudinal axis which is disposed at an angle with the support surface and with the path of such longitudinal and transverse movement.

Although the invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention as hereinafter claimed.

What is claimed is:

1. In an X-ray table having a body with a support surface and a column mounted in the body for relative longitudinal and transverse movement in a path paralleling the surface, the combination of, an X-ray tube housing mounted on the column and disposed within the body said housing having a longitudinal axis disposed at an acute angle with said support surface and the path of such longitudinal and transverse movement, and an X-ray tube within the housing oriented to emit a beam symmetrically about an imaginary line normal to such path and the surface.

2. In an X-ray table having a body with a support surface and a column mounted in the table for relative longitudinal movement, the combination of, an X-ray tube housing mounted on the column and disposed within the body, an X-ray tube disposed within the housing and having a rotatable anode and a cathode, said cathode being positioned to bombard a target area on said anode with a flow of electrons in a beam having a center line generally normal to the support surface, and said anode having an axis of rotation between said target area and said support surface and at an angle with said support surface.

3. An X-ray table comprising,

(a) a pedestal;

(b) a hollow body mounted on the pedestal and including a base wall and end walls tapering inwardly adjacent the base wall;

(c) the body having a support surface;

(d) a column mounted in the table for movement along transverse and longitudinal paths paralleling the table surface;

(e) an X-ray tube housing carried by the column and having a longitudinal axis at an acute angle with the surface and the path of travel;

(1) an X-ray tube within the housing and oriented to emit a beam of X-rays along a path generally normal to the table surface;

(g) said housing being positioned such that it nests against one of the end walls with one end of the tube abutting the end wall at a first location spaced from the base wall; and,

(It) said housing having another end nearer the base wall and positioned to abut the other of said end walls at a second location nearer the base wall than the first location.

4. The device of claim 2 wherein the target area is symmetrically disposed about an imaginary plane including such axis of rotation and normal to such surface.

5. In an X-ray table having a pedestal, a body with a support surface tiltably carried by the pedestal and a column mounted in the body for relative longitudinal transverse movement, the combination of, an X-ray tube housing disposed within the body and mounted on the column for movement therewith relative to the body, an X-ray tube within the housing, the housing and tube having a longitudinal axis disposed at an angle with said support surface and the path of such lateral movement, the tube including a rotatable anode and a cathode positioned to bombard a target area on the anode, and said target area being positioned with the axis of anode rotation between the area and said support surface.

6. An X-ray apparatus comprising a pedestal, a table body movably mounted on said pedestal, the body having a support surface, means interposed between the body and the pedestal for tilting the body relative to the pedestal from a horizontal to a vertical position and return while simultaneously shifting the body translationally along a path paralleling the table surface, a column mounted in the table with the mounting on one side of said surface which side is beneath said surface when the surface is horizontal, said column being longitudinally and transversely movable relative to said body, an X-ray tube housing carried by said column within said body on said one side of said surface, an X-ray responsive element carried by the column and above said surface when the surface is horizontal, an X-ray tube within the housing and having a rotatable anode, the anode including a frusto-conical target, said tube having a cathode positioned to bombard an area on the inner surface of said fmsto cone, said anode having an axis of rotation at an acute angle with respect to said surface and between said target area and said surface, and cables connected to said housing.

7. The device of claim 6 wherein the angle of the anode axis is at a sufficient angle with the surface to place the portion of the frusto-cone opposite the target area free of a cone of emitted rays of the greatest apex angle required for operation of the apparatus.

8. An X-ray table comprising a pedestal, a body movably m-ounted on said pedestal, means interposed between the body and the pedestal for tilting the body relative to the pedestal f-nom a horizontal to a vertical position and return and simultaneously moving the body translationally, the body having a support surface, a column mounted in the table with the mounting on one side of said surface, which side is beneath said surface when the surface is horizontal, said column being longitudinally and trans versely movable relative to said body, an X ray tube housing carried by said column on said one side of said surface and within said body, a ray responsive sheet carried by the column on the other side of said surface, an X-ray tube within the housing and having a rotatable anode,

said tube having a cathode positioned to bombard a target area on said anode, said anode having an axis of rotation at an acute angle with respect to said surface and between said target area and said surface, movable X-ray impervious diaphragms paralleling the body surface and carried by the column between the tube and the body surface, the diaphragms delimiting the cross sectional area of an emitted beam impinged on an object under study, said angle of the axis of rotation being suthcient to maintain the portion of the anode opposite said target area out of the path of such delimited beam in all operating positions, and electric cab'les connected to said housing and electrically connected to the tube.

9. An X-ray table comprising, a pedestal, a table body pivotally mounted on said pedestal and shiftable translationally relative to the pedestal, said table body including an upper support surface located in a planepara'lleling the path of such translational shifting, longitudinal guides within the table body and paralleling said surface, a carriage mounted on the guides for longitudinal travel therealong, said body including an elongated carriage opening at the rear thereof, a fluoroscopic column including a carrier projecting through the elongated opening and carried by the carriage, said carrier and column being reciprocal transversely of the table top and relative to said carriage, an X-ray tube support carried by the carrier and disposed within the body, an X-ray tube housing carried by the support and also disposed within the table body, said tube support being between the housing and the carrier, the carrier and the support each being between the housing and said surface, said housing including an X-ray window; an X-ray tube positioned within the housing and oriented to emit a beam of X-rays through said window, said tube support, said carrier, and said surface for the conduction of an X-ray examination; said X-ray tube including a rotatable anode having an axis of rotation coincident with the longitudinal axis of the X-ray housing, said coincident axes being at an angle with said surface, and said anode including a target area positioned with said coincident axes between the target area and the table top.

10. An X-ray apparatus comprising a pedestal, a table body movably mounted on said pedestal, means interposed between the body and the pedestal for tilting the body relative to the pedestal from a horizontal to a vertical position and return, the body having a support surface, a column mounted in the table with the mounting on one side of said surface which side is beneath said surface when the surface is horizontal, said column being ilongitudinally and transversely movable relative to said body, an X-ray tube housing carried by said column on said one side of said surface and within said body, a ray responsive sheet carried by the column on the other side of said surface, an X-ray tube within the housing and having a rotatable anode, said tube having a cathode positioned to bombard a target area on said anode and cause a beam of X-rays to be emitted along a path generally normal to the support surface, said anode having an axis of rotation at an acute angle with respect to said surface and between said target area and said surface, and cables connected to said housing and extending through a wall of the body for connection to a source of electric potential.

11. The device of claim 10 wherein the cables have end connections disposed in opposite directions and on opposite sides of such axis of rotation.

12. The device of claim 11 wherein the end connections are disposed symmetrically about an imaginary plane located by the axis of rotation and a horizontal line intersecting such axis.

13. The device of claim 10 wherein the table has a fiat base and spaced ends slanted inwardly adjacent the base, and wherein one end of the housing lies adjacent the base and the other is spaced therefrom and wherein the coaction of said other housing end and an imaginary line of intersection on one of the table ends and spaced upwardly from'the basedelimits'the extent of column movement in one direction.

14. A housing for anX-ray tube comprising, an elon gated central portion defining an X-ray tube receiving cavity, said central portion including a windowdisposed centrally thereof and communicating with said cavity, first and second cable connection arms projecting onopposite sides of the .body central portion and disposed along paths generally paralleling the longitudinal axis of the housing, said arms including electrical terminal receiving receptacles oriented in opposite directions and terminating in end openings near the longitudinal midpoint of said central portion, said housing including passageways providing communication between said receptacles and said cavity, conductors in said passageway for respective-1y connecting each end of the tube receiving cavity with one of the receptacles, and said arms-and said central portion each having longitudinal axes generally paralleling one another and the tube receiving cavity and generally normal to the axis of the X-ray window.

15. The device of claim 14 wherein the arms are disposed on opposite sides of an imaginary plane bisecting said window and including the longitudinal axis of the central portion and wherein'said arms are equal distances from such plane.

16. The device of claim 14 wherein the housing includes anode and cathode sections, wherein each such section includes one arm and a part of said centralportions and wherein said sections are relatively rotatable about the longitudinal axis of the central portion and a means is provided to fix the two sections in a selected relative position to orient the arms relative to one another.

17. The device of claim 15 wherein the tube includes a rotatable anode including a'target area and an axis of rotation between the target area and the support surface and substantially coincident with said housing longitudinal axis.

18. An X-ray table comprising,

(a) a pedestal;

(b) a hollow body mounted on the pedestal and including a base wall and end walls tapering inwardly adjacent the base wall;

(0) the body'having a support surface;

(d) a column mounted in the table for movement along transverse and longitudinal paths paralleling the table surface;

(e) an X-ray tube housing carried by the column and having a'longitudinal axis at an acute angle with the surface and the path of travel;

( an X-ray tube within the housing and oriented to emit a beam of X-rays along'a path generally normal to the table surface;

(.g) said housing comprising:

-(i) an elongated central portion defining an X-ray tube receiving cavity and including a window disposed centrally thereof and communicating with said cavity;

(ii) first and second cable connection arms projecting on opposite sides of the body central portion and disposed along paths generallyparalleling the longitudinal axis of the housing;

(iii) said arm-s including electrical terminal receiving receptacles oriented in opposite directions and terminating in end openings near the longitudinal midpoint of said central portion;

(iv) said housing including passagewaysproviding communication between said receptacles and said cavity;

(v) conductors in said passageway for respectively connecting each end of the tube receiving cavity with one of the receptacles;

(vi) said central portion including an axis coincident with a part of the housing longitudinal axis; and,

(vii) said arms having longitudinal axes generally paralleling another and the longitudinal axis of the housing and generally normal to the axis of the X-ray window.

References Cited in the file of this patent UNITED STATES PATENTS 1,594,171 Grobe July 27, 1926 1,624,331 Geyser Apr. 12, 1927 1,828,092 Wantz et a1. Oct. 20, 1931 10 Pohl May 7, 1935 Bouwers et al Jan. 14, 1941 Allibone Aug. 11, 1942 Grobe Apr. 6, 1943 Koerner et al June 28, 1955 Kizaur Dec. 27, 1960 FOREIGN PATENTS Germany Aug. 19, 1940 

1. IN AN X-RAY TABLE HAVING A BODY WITH A SUPPORT SURFACE AND A COLUMN MOUNTED IN THE BODY FOR RELATIVE LONGITUDINAL AND TRANSVERSE MOVEMENT IN A PATH PARALLELING THE SURFACE, THE COMBINATION OF, AN X-RAY TUBE HOUSING MOUNTED ON THE COLUMN AND DISPOSED WITHIN THE BODY SAID HOUSING HAVING A LONGITUDINAL AXIS DISPOSED AT AN ACUTE ANGLE WITH SAID SUPPORT SURFACE AND THE PATH OF SUCH LONGITUDINAL AND TRANSVERSE MOVEMENT, AND AN X-RAY TUBE WITHIN THE HOUSING ORIENTED TO EMIT A BEAM SYMMETRICALLY ABOUT AN IMAGINARY LINE NORMAL TO SUCH PATH AND THE SURFACE. 